.\"***************************************************************************
.\" Copyright (c) 1998,2002 Free Software Foundation, Inc.                   *
.\"                                                                          *
.\" Permission is hereby granted, free of charge, to any person obtaining a  *
.\" copy of this software and associated documentation files (the            *
.\" "Software"), to deal in the Software without restriction, including      *
.\" without limitation the rights to use, copy, modify, merge, publish,      *
.\" distribute, distribute with modifications, sublicense, and/or sell       *
.\" copies of the Software, and to permit persons to whom the Software is    *
.\" furnished to do so, subject to the following conditions:                 *
.\"                                                                          *
.\" The above copyright notice and this permission notice shall be included  *
.\" in all copies or substantial portions of the Software.                   *
.\"                                                                          *
.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
.\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
.\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
.\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
.\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
.\" THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
.\"                                                                          *
.\" Except as contained in this notice, the name(s) of the above copyright   *
.\" holders shall not be used in advertising or otherwise to promote the     *
.\" sale, use or other dealings in this Software without prior written       *
.\" authorization.                                                           *
.\"***************************************************************************
.\"
.\" $Id: form_driver.3x,v 1.9 2002/02/16 22:39:52 tom Exp $
.TH form_driver 3X ""
.SH NAME
\fBform_driver\fR - command-processing loop of the form system
.SH SYNOPSIS
\fB#include <form.h>\fR
.br
int form_driver(FORM *form, int c);
.br
.SH DESCRIPTION
Once a form has been posted (displayed), you should funnel input events to it
through \fBform_driver\fR.  This routine has two major input cases; either
the input is a form navigation request or it's a printable ASCII character.
The form driver requests are as follows:
.TP 5
REQ_NEXT_PAGE
Move to the next page.
.TP 5
REQ_PREV_PAGE
Move to the previous page.
.TP 5
REQ_FIRST_PAGE
Move to the first page.
.TP 5
REQ_LAST_PAGE
Move to the last field.

.TP 5
REQ_NEXT_FIELD
Move to the next field.
.TP 5
REQ_PREV_FIELD
Move to the previous field.
.TP 5
REQ_FIRST_FIELD
Move to the first field.
.TP 5
REQ_LAST_FIELD
Move to the last field.
.TP 5
REQ_SNEXT_FIELD
Move to the sorted next field.
.TP 5
REQ_SPREV_FIELD
Move to the sorted previous field.
.TP 5
REQ_SFIRST_FIELD
Move to the sorted first field.
.TP 5
REQ_SLAST_FIELD
Move to the sorted last field.
.TP 5
REQ_LEFT_FIELD
Move left to a field.
.TP 5
REQ_RIGHT_FIELD
Move right to a field.
.TP 5
REQ_UP_FIELD
Move up to a field.
.TP 5
REQ_DOWN_FIELD
Move down to a field.

.TP 5
REQ_NEXT_CHAR
Move to the next char.
.TP 5
REQ_PREV_CHAR
Move to the previous char.
.TP 5
REQ_NEXT_LINE
Move to the next line.
.TP 5
REQ_PREV_LINE
Move to the previous line.
.TP 5
REQ_NEXT_WORD
Move to the next word.
.TP 5
REQ_PREV_WORD
Move to the previous word.
.TP 5
REQ_BEG_FIELD
Move to the beginning of the field.
.TP 5
REQ_END_FIELD
Move to the end of the field.
.TP 5
REQ_BEG_LINE
Move to the beginning of the line.
.TP 5
REQ_END_LINE
Move to the end of the line.
.TP 5
REQ_LEFT_CHAR
Move left in the field.
.TP 5
REQ_RIGHT_CHAR
Move right in the field.
.TP 5
REQ_UP_CHAR
Move up in the field.
.TP 5
REQ_DOWN_CHAR
Move down in the field.

.TP 5
REQ_NEW_LINE
Insert or overlay a new line.
.TP 5
REQ_INS_CHAR
Insert a blank at the cursor.
.TP 5
REQ_INS_LINE
Insert a blank line at the cursor.
.TP 5
REQ_DEL_CHAR
Delete character at the cursor.
.TP 5
REQ_DEL_PREV
Delete character before the cursor.
.TP 5
REQ_DEL_LINE
Delete line at the cursor.
.TP 5
REQ_DEL_WORD
Delete blank-delimited word at the cursor.
.TP 5
REQ_CLR_EOL
Clear to end of line from cursor.
.TP 5
REQ_CLR_EOF
Clear to end of field from cursor.
.TP 5
REQ_CLR_FIELD
Clear the entire field.
.TP 5
REQ_OVL_MODE
Enter overlay mode.
.TP 5
REQ_INS_MODE
Enter insert mode.

.TP 5
REQ_SCR_FLINE
Scroll the field forward a line.
.TP 5
REQ_SCR_BLINE
Scroll the field backward a line.
.TP 5
REQ_SCR_FPAGE
Scroll the field forward a page.
.TP 5
REQ_SCR_BPAGE
Scroll the field backward a page.
.TP 5
REQ_SCR_FHPAGE
Scroll the field forward half a page.
.TP 5
REQ_SCR_BHPAGE
Scroll the field backward half a page.

.TP 5
REQ_SCR_FCHAR
Scroll the field forward a character.
.TP 5
REQ_SCR_BCHAR
Scroll the field backward a character.
.TP 5
REQ_SCR_HFLINE
Horizontal scroll the field forward a line.
.TP 5
REQ_SCR_HBLINE
Horizontal scroll the field backward a line.
.TP 5
REQ_SCR_HFHALF
Horizontal scroll the field forward half a line.
.TP 5
REQ_SCR_HBHALF
Horizontal scroll the field backward half a line.

.TP
REQ_VALIDATION
Validate field.
.TP
REQ_NEXT_CHOICE
Display next field choice.
.TP
REQ_PREV_CHOICE
Display previous field choice.
.PP
If the second argument is a printable ASCII character, the driver places it
in the current position in the current field.  If it is one of the forms
requests listed above, that request is executed.
.PP
If the second argument is neither printable ASCII nor one of the above
pre-defined form requests, the driver assumes it is an application-specific
command and returns \fBE_UNKNOWN_COMMAND\fR.  Application-defined commands
should be defined relative to \fBMAX_COMMAND\fR, the maximum value of these
pre-defined requests.
.SH RETURN VALUE
\fBform_driver\fR return one of the following error codes:
.TP 5
\fBE_OK\fR
The routine succeeded.
.TP 5
\fBE_SYSTEM_ERROR\fR
System error occurred (see \fBerrno\fR).
.TP 5
\fBE_BAD_ARGUMENT\fR
Routine detected an incorrect or out-of-range argument.
.TP 5
\fBE_BAD_STATE\fR
Routine was called from an initialization or termination function.
.TP 5
\fBE_NOT_POSTED\fR
The form has not been posted.
.TP 5
\fBE_UNKNOWN_COMMAND\fR
The form driver code saw an unknown request code.
.TP 5
\fBE_INVALID_FIELD\fR
Contents of field is invalid.
.TP 5
\fBE_REQUEST_DENIED\fR
The form driver could not process the request.
.SH SEE ALSO
\fBcurses\fR(3X), \fBform\fR(3X).
.SH NOTES
The header file \fB<form.h>\fR automatically includes the header files
\fB<curses.h>\fR.
.SH PORTABILITY
These routines emulate the System V forms library.  They were not supported on
Version 7 or BSD versions.
.SH AUTHORS
Juergen Pfeifer.  Manual pages and adaptation for new curses by Eric
S. Raymond.
.\"#
.\"# The following sets edit modes for GNU EMACS
.\"# Local Variables:
.\"# mode:nroff
.\"# fill-column:79
.\"# End:
